I have a 2004 jeep grand cheockee v6 4.0
I have to turn the key on and off several times for it
to start then I start driving it and it starts bucking
and skipping what could be the problem
My educated guess would be your fuel pump is not producing enough pressure. There are pressure testers at the local parts stores some even for rent. Just google your vehicle fuel pressure specs and see where you are at before you throw a bunch of money at a problem.